Someone (machi-) competes, races with someone or something to defeat the other.
Machiābak ako dyimo do kapayayo.
I race with you in running.
Someone (mang-) wins against someone or something (-en) as an argument, a contest, a game, gambling, a decision of law, etc.
ábak
talo
humis
Maganay ako a magposta, ta kanayon ako a mangābak.
I am good at making bets, because I always win.
Someone (ma-) is defeated, loses in something.
parmék
talo
humis
Naābak si āmang so dadima kapisos.
Father lost five pesos (in gambling).